Potomac named America's most endangered river

The Potomac River, which flows between Maryland and Virginia, was named the nation's "most endangered" waterway today by a Washington-based environmental group.

American Rivers put the Potomac atop its annual list of endangered rivers. Though cleaner than it used to be, the "nation's river," so named because it flows through Washington, D.C., still faces threats from urban and agricultural pollution, the group says, and from cutbacks being pushed in Congress of federal environmental regulations.

Before Congress passed the Clean Water Act in 1972, the Potomac was fouled by untreated sewage and industrial pollution. The law prompted sewage plant upgrades and controls on industrial discharges on the Potomac and other rivers nationwide. But the University of Maryland report card on the Chesapeake Bay's health has given the Potomac a "D" for its water quality the past two years.

“The Clean Water Act is the reason the Potomac River is no longer called a 'national disgrace.'" Ed Merrifield, president of Potomac Riverkeeper, said in a statement. "Most of the palpable problems are gone; however, there are many emerging threats that can't be seen. Residents of the Washington D.C. metro area– including the President and Congress– need to realize they are composed mostly of Potomac river water and they need to protect and enforce the laws that safeguard their health.”

This is the second time in three years that the Potomac has made American Rivers' most endangered list. In 2009, the group listed Mattawoman Creek, a Potomac tributary.

Other rivers on the 2012 endangered list, and the group's identifcation of threats to their health, are:

- Green River, a tributary of the Colorado River, for water withdrawals;

- Chattahoochee River in Georgia, for new dams and reservoirs;

- Missouri River in the Great Plains, for outdated flood management;

- Hoback River in Wyoming, for potential threats from natural gas drilling;